The species of the favourite genus Primula which we have here represented, is a very elegant one; and greatly resembles P. cortusifolia, which is figured on our 7th plate; but differs from it in the extraordinary denticulations of the flowers; which we have been assured are a constant and permanent character of the plant, and, if so, affords an excellent and decisive mark of specific distinction, and at the same time a trivial name of undeniable goodness. We have not been able to ascertain with any kind of certainty its native place of growth. It was communicated to us in bloom in the month of September last, from the select collection of Lady de Clifford, at Paddington, and is found to be a hardy plant, and to succeed with the treatment of the other Primulæ; that is, as an alpine plant in bog earth, and a small portion of loam; and protected in summer from the mid-day and afternoon, but not the morning or evening sun. It is propagated by parting the roots in autumn; and as a new and at the same time beautiful Primula, it cannot fail to be acceptable to all our subscribers. [Illustration] PLATE CCCCVI. APONOGETON MONOSTACHYON. _Simple-spiked Aponogeton._ CLASS XI. ORDER IV. _DODECANDRIA TETRAGYNIA._ Twelve Chives. Four Pointals. ESSENTIAL GENERIC CHARACTER. AMENTUM e squamis compositum. Calyx nullus. Corolla nulla. Capsulæ 4, trispermæ. CATKIN composed of scales. Empalement none. Blossom none. Capsules 4, three-seeded. SPECIFIC CHARACTER, &C. APONOGETON, spicâ simplici, foliis cordato-ovalibus. _Willd. Sp. Pl. 2. 927._ APONOGETON, with a simple spike, and heart-oval shaped leaves. REFERENCE TO THE PLATE. 1. The chives detached. 2. The pointals detached. 3. The same magnified. Four species only of this singular genus have hitherto been enumerated by authors: viz. the present one from the East Indies; crispum, a native of Ceylon; and angustifolium and distachyon, from the Cape of Good Hope; the last of which is the most showy, and is figured on our 290th plate. They are all water plants, and could no more thrive with their roots and natant leaves out of that element than an Aloe or Stapelia could prosper in it: they are therefore, along with other tropical aquatics, cultivated in our hot-houses in troughs or cisterns of rich earth and clear water; in which, consociated with the majestic Nymphææ, the stately Thalia, and the more humble but not less interesting Menyanthes indica, they produce a most fragrant and desirable appearance; that perhaps is indebted for some of its charms to the fine contrast formed by the terrestrial exotics which surround them.